Electric and gas water heaters are commonly used to provide a reserve of heated water for residential or commercial use. A typical water heater includes inlet piping for supplying cold water to a water tank and outlet piping for supplying heated water to one or more dispensing locations. In normal operation of the water heater, significant heat is lost through the inlet and outlet piping during stand-by periods when the tank is not being actively heated. This heat loss is primarily through thermal convection currents within the water. In other words, heat from the tank transfers in a vertical direction out of the tank within the inlet and outlet piping. Consequently, it is known in the art to use a heat trap assembly installed in the inlet and outlet piping above the tank as an energy saving device to reduce energy loss.
Typical heat trap designs are directed to damming the thermal convection currents. Several known designs have certain inherent flaws, including undesirable flow restriction, single direction installation capability, and limited longevity due to a propensity for corrosion of parts or subassemblies. Still other conventional heat traps include ball valves. Heat traps of this design create an undesirable rattling or clicking noise in operation as the ball contacts the internal pipe wall and/or the valve seat.
The present invention provides a new and improved heat trap assembly. The assembly provides a thermal barrier while permitting increased flow over prior art designs. The design is not flow directional specific, thereby increasing ease of installation by permitting installation in two directions. Moreover, the device can be installed in a horizontal or a vertical plane, or in any other orientation between horizontal and vertical. The materials used in the assembly are non-corrodible or corrosion resistant and thus do not decrease or otherwise limit the longevity of the device. The device also offers virtually silent operation. Another important feature is the device is self-regulating in regard to flow demand. Further, the present invention is highly adaptable to a variety of related applications. For example, the device may be inserted in field repairs by a technician, installed by a home owner as an after-market add-on device, or included in a water heater bill-of-material by an original equipment manufacturer.